Upgrade to boost 1.81.0

Per the other commits, we are temporarily moving to boost 1.81.0 to get
ahead of some of the API breaking changes in boost-url.  This requires
moving CI off of using the yocto mirror.  So far as I'm aware, the boost
bandwidth issues have been long solved, so this should be fine.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: Iec89a040374bef52c5188c89be9f8a25a12d6164
diff --git a/scripts/build-unit-test-docker b/scripts/build-unit-test-docker
index 4b79799..b09cd5e 100755
--- a/scripts/build-unit-test-docker
+++ b/scripts/build-unit-test-docker
@@ -80,9 +80,9 @@
 # Packages to include in image.
 packages = {
     "boost": PackageDef(
-        rev="1.80.0",
+        rev="1.81.0",
         url=(
-            lambda pkg, rev: f"https://downloads.yoctoproject.org/mirror/sources/{pkg}_{rev.replace('.', '_')}.tar.bz2"  # noqa: E501
+            lambda pkg, rev: f"https://boostorg.jfrog.io/artifactory/main/release/{rev}/source/{pkg}_{rev.replace('.', '_')}.tar.gz"  # noqa: E501
         ),
         build_type="custom",
         build_steps=[
@@ -168,12 +168,6 @@
         rev="9.0.0",
         build_type="cmake",
     ),
-    # version from /meta-openembedded/meta-oe/recipes-devtools/boost-url/boost-url_git.bb # noqa: E501
-    "CPPAlliance/url": PackageDef(
-        rev="d740a92d38e3a8f4d5b2153f53b82f1c98e312ab",
-        build_type="custom",
-        build_steps=[f"cp -a include/** {prefix}/include/"],
-    ),
     "tristanpenman/valijson": PackageDef(
         rev="v0.7",
         build_type="cmake",